Stereolithography (SLA)
Stereolithography uses a UV laser to cure photopolymer resin layer by layer. A build platform sits in a vat of uncured liquid resin and can move upwards and downwards. A layer of resin (thickness of the specified printing layer) is spread over the platform and a laser scans this platform to photopolymerize and solidify it. The surrounding liquid resin maintains a cooler temperature so that it stays liquid while the laser scans it. The laser’s position is controlled by a scanning mirror that specifies and directs the laser to the coordinates of the areas it needs to hit. After solidification, the platform moves in layer-thick increments for the subsequent curing of the next layer. The layer thickness of SLA printed parts ranges from 25 to 100 microns.